Rainfall trends in the Badia Region of Jordan

In Jordan, like in other semi-arid countries in the region, water resources are increasingly becoming an important factor in its stability, growth, and national security. This study examines the rainfall record of 25 stations during the period 1967-1995 to determine periodicity and interrelations between stations using power spectral, harmonic analysis, and correlation coefficient techniques. The ARIMA model is used to forecast rainfall trends in individual stations up to the year 2020. The outcomes show that the intensity of rainfall has been decreasing with time since 1967, and this trend is likely to continue into the future. The average annual rainfall is relatively low (90 mm/y), and there are some significant differences in rainfall values between the stations due mainly to topography. Stations with the same altitude that are close geographically tend to have a strong statistical association and show a similar rainfall trend. Furthermore, a statistically significant relationship was established between vegetation index (derived from remotely sensed data) and rainfall intensity. The outcomes from this study can be used as a basis for planning future agricultural, economic, and social development in Jordan and in the Badia region, in particular